[issybird]

American, no blood and gore, no romance, no sex:

Probably my very favorite of all, the Nero Wolfe mysteries by Rex Stout. They are quirky and funny and as much about the relationship between Wolfe and his sidekick/narrator, Archie Goodwin as about solving the mystery. The classic Holmes/Watson pairing.

I can also be entertained by the Ellery Queen mysteries by Ellery Queen, especially the Golden Age era ones. Meets all your parameters.

Joan Hess had a couple of entertaining series. The Claire Malloy books are a straight-up mystery series; the "Maggody" ones set in Arkansas are hilarious. There's a little mild romance, but the romance isn't the point.